1998 GMC ENVOY service

NOTICE: (Continued)
If your tires have too much air (overinflation),
you can get the following:
0 Unusual wear
Bad handling
Rough ride
Needless damage from road hazards.
When to Check
Check your tires once a month or more. Also, check the
tire pressure
of the spare tire.
How to Check
Use a good quality pocket-type gage to check tire
pressure. You can’t
tell if your tires are properly inflated
simply by looking at them. Radial tires may look
properly inflated even when they’re underinflated.
Be sure to put the valve caps back on the valve stems.
They help prevent leaks by keeping out dirt and moisture.
Tire Inspection and Rotation
Tires should be rotated every 6,000 to 8,000 miles
( 10 000 to 13 000 km). Any time you notice unusual
wear, rotate your tires
as soon as possible and check
wheel alignment.
Also check for damaged tires or
wheels. See “When It’s Time for New Tires” and
“Wheel Replacement” later in
this section for
more information.
The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. The first
rotation is the most important. See “Scheduled
Maintenance Services”
in the Index for scheduled
rotation intervals.
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When It’s Time for New Tires
One way to tell when it’s
time for new tires is to
check the treadwear
indicators, which will
appear when your tires have
only 1/16 inch (1.6 mm) or
less
of tread remaining.
You need a new tire if any of the following statements
are true:
0 You can see the indicators at three or more places
around the tire.
You can see cord or fabric showing through the
tire’s rubber.
The tread or sidewall is cracked, cut or snagged deep
enough to show cord or fabric.
0 The tire has a bump, bulge or split.
The tire has a puncture, cut or other damage that
can’t be repaired well because of the size or location
of the damage.
Buying New Tires
To find out what kind and size of tires you need, look at
the Certificationmire label.
The tires installed
on your vehicle when it was new had
a Tire Performance Criteria Specification (TPC Spec)
number on each tire’s sidewall. When
you get new tires,
get ones with that same TPC Spec number. That way
your vehicle will continue to have tires that are designed
to give proper endurance, handling, speed rating,
traction, ride and other things during normal service
on
your vehicle. If your tires have an all-season tread
design, the TPC number will be followed by an
“MS”
(for mud and snow).
If you ever replace your tires with those not having a
TPC Spec number, make sure they are the same size,
load range, speed rating and construction type (bias,
bias-belted or radial)
as your original tires.
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Treadwear Temperature -- A, B, C
The
treadwear grade is a comparative rating based on
the wear rate of the tire when tested under controlled
conditions
on a specified government test course. For
example,
a tire graded 150 would wear one and a half
(1 1/2) times as well on the government course as a tire
graded
100. The relative performance of tires depends
upon the actual conditions
of their use, however, and
may depart significantly from the norm due to variations
in driving habits, service practices and differences in
road characteristics and climate.
Traction -- A, B, C
The traction grades, from highest to lowest, are A, B,
and C, and they represent the tire’s ability to stop on
wet pavement
as measured under controlled conditions
on specified government test surfaces
of asphalt and
concrete.
A tire marked C may have poor
traction performance.
Warning: The traction grade assigned to this tire is based
on braking (straight ahead) traction tests and does not
include cornering (turning) traction. The
temperature grades are
A (the highest), B, and C,
representing the tire’s resistance to the generation of
heat and its ability to dissipate heat when tested under
controlled conditions on
a specified indoor laboratory
test wheel. Sustained high temperature can cause the
material of the tire to degenerate and reduce tire life,
and excessive temperature can lead to sudden
tire
failure. The grade C corresponds to a level of
performance which all passenger car tires must meet
under the Federal Motor Vehicle Safety Standard
No. 109. Grades B and A represent higher levels of
performance on the laboratory test wheel than the
minimum required by law.
Warning: The temperature grade for this tire is
established for a tire that is properly inflated and not
overloaded. Excessive speed, underinflation, or
excessive loading, either separately or in combination,
can cause heat buildup and possible tire failure.
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Finish Damage
Any stone chips, fractures or deep scratches in the finish
should be repaired right away. Bare metal will corrode
quickly and may develop into a major repair expense.
Minor chips and scratches can be repaired with touch-up
materials available from your dealer or other service
outlets. Larger areas
of finish damage can be corrected
in your dealer’s body and paint shop.
Underbody Maintenance
Chemicals used for ice and snow removal and dust
control can collect on the underbody.
If these are not
removed, accelerated corrosion (rust) can occur
on
the underbody parts such as fuel lines, frame, floor
pan and exhaust system even though they have
corrosion protection.
At least every spring, flush these materials from the underbody with plain water. Clean any areas where mud
and other debris can collect. Dirt packed in closed areas
of the frame should be loosened before being flushed.
Your dealer or an underbody car washing system can do
this for you.
Chemical Paint Spotting
Some weather and atmospheric conditions can create
a chemical fallout. Airborne pollutants can fall upon
and attack painted surfaces on your vehicle. This
damage can take two forms: blotchy, ringlet-shaped
discolorations, and small irregular dark spots etched into
the paint surface.
Although no defect in the paint job causes this,
GMC
will repair, at no charge to the owner, the surfaces of
new vehicles damaged by this fallout condition within
12 months or 12,000 miles (20 000 km) of purchase,
whichever occurs first.
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Vehicle Identification Number (VIN)
Gl SAMPLE4UXWM072675 Gl
This is the legal identifier for your vehicle. It appears on
a plate in the front corner of the instrument panel, on the
driver’s side. You can see it
if you look through the
windshield from outside your vehicle. The
VIN also
appears on the Vehicle Certification and Service Parts
labels and the certificates
of title and registration.
Engine Identification
The 8th character in your VIN is the engine code. This
code will help you identify your engine, specifications
and replacement parts.
Service Parts Identification Label
You‘ll find this label on the inside of the glove box. It’s
very helpful if you ever need to order parts. On this
label
is:
0 your VIN,
0 the model designation,
0 paint information and
0 a list of all production options and
special equipment.
Be sure that
this label is not removed from the vehicle.
Electrical System
Add-on Electrical Equipment
NOTICE:
Don’t add anything electrical to your vehicle
unless you check with
your dealer first. Some
electrical equipment can damage your vehicle
and the damage wouldn’t be covered by your
warranty. Some add-on electrical equipment
can keep other components from working as
they should.
Your vehicle has an air bag system. Before attempting to
add anything electrical to your vehicle, see “Servicing
Your
Air Bag-Equipped Vehicle” in the Index.
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Section 7 Maintenance Schedule
This section covers the maintenance required for your vehicle. Your vehicle needs these services to retain its safety,
dependability and emission control performance.
7-2
7-4
7-5
7-5
7-6
7-6 Introduction
Part
A: Scheduled Maintenance Services
Short Trip/City Definition
Short Trip/City Intervals
Long Trip/Highway Definition
Long Trip/Highway Intervals
7-7
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7-45
7-47
Short Trip/City Maintenance Schedule
Long Trip/Highway Maintenance Schedule
Part
B: Owner Checks and Services
Part
C: Periodic Maintenance Inspections
Part
D: Recommended Fluids and Lubricants
Part
E: Maintenance Record
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I I M PORTANT:
KEEP ENGINE OIL
I
AT THE PROPER
LEVEL AND CHANGE AS
RECOMMENDED
Protection
Plan
Introduction
Your Vehicle and the Environment
Proper vehicle maintenance not only helps to keep your
vehicle
in good working condition, but also helps the
environment. All recornmended maintenance procedures
are inymrtant. Improper vehicle maintenance can even
affect the quality
of the air we breathe. Improper fluid
levels or the wrong tire inflation can increase the level
of emissions fro111 your vehicle. To help protect OLI~
environment. and to keep your vehicle in good
condition, please maintain your vehicle properly.
How This Section is Organized
The remainder of this section is divided into five parts:
“Part A: Scheduled Maintenance Services” shows
what to have done and
how often. Some of these
services can be complex,
so unless you are technically
qualified and have
the necessary equipment, you should
let your dealer‘s service department
or another qualified
service center
do these jobs.
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A
A CAUTION:
Performing maintenance work on a vehicle can
be dangerous. In trying to do some .jobs, you can
be seriously injured.
Do your own maintenance
work only
if you have the required know-how
and the proper tools and equipment for the job.
If you have any doubt, have a qualified
technician do the
work.
If you are skilled enough to do some work on your
vehicle, you will probably want to get the service
information. See “Service and Owner Publications“
in
the Index. “Part
B: Owner Checks and Services”
tells you what
should be checked and when.
It also explains what you
can easily do to help keep your \:chicle in good condition.
“Part C: Periodic Maintenance Inspections” explains
important inspections that
YOLK dealer’s service department
or another qualified service center should perform.
“Part
D: Recommended Fluids and Lubricants” lists
so~ne recommended products to help keep
your vehicle
properly maintained. These products. or their
equivalents, should be used whether you
do the work
yourself
or have it done.
“Part
E: Maintenance Record” provides a place for
you to ~-eco~-d the maintenance performed on your
vehicle. Whenever any maintenance is performed, be
sure to write
it down in this part. This will help you
determine when your next maintenance should be done.
In addition. it is a good idea to keep your maintenance
receipts. They may be needed to qualify your vehicle for
warranty repairs.
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